Pro-Coil W/ Yellow Wire HEI

The Pro-Coil with Yellow Wire HEI by Moroso is a high-performance ignition coil engineered for street and racing applications where reliable spark delivery and precise timing control are non-negotiable. Built for engines running HEI (High Energy Ignition) distributors, this coil serves enthusiasts and mechanics who demand consistent ignition performance across a wide RPM range. Whether you're tuning a classic muscle car, optimizing a street rod, or maintaining a well-sorted performance engine, the Pro-Coil delivers the electrical intensity needed to fire stubborn or high-compression cylinders reliably.

This coil features Moroso's proven design optimized for HEI systems, with the yellow primary wire enabling straightforward integration into existing distributor harnesses without adapter complexity. The compact form factor—measuring 3.9 x 2.95 x 5.1 inches and weighing just 1.77 lbs—fits tight engine bays while its robust construction handles thermal cycling and vibration inherent to performance driving. The yellow wire convention simplifies installation and diagnostics, allowing technicians and builders to quickly verify proper connections and troubleshoot ignition circuits without guesswork or reference manuals.

Pro-Coil HEI units are ideal for owners of small-block and big-block Chevrolet engines, Pontiacs, and other vehicles originally equipped with HEI or retrofitted to run HEI distributor systems. Installation requires only basic mechanical skills—secure the coil in a clean, heat-managed location and connect the primary (yellow) and secondary (spark plug wires) terminals. For best results, pair with quality spark plug wires and a well-tuned ignition curve; proper gap setting and timing will maximize the coil's potential and improve cold-start reliability, throttle response, and fuel economy across all driving conditions.